Add decode data method in Tx Service Api

[falvaradorodriguez]

Closes #1006

[coveralls]

Pull Request Test Coverage Report for Build 9304382134

Details

• 16 of 17 (94.12%) changed or added relevant lines in 2 files are covered.
• 2 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.02%) to 93.499%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
gnosis/safe/api/transaction_service_api/transaction_service_api.py	7	8	87.5%

Files with Coverage Reduction	New Missed Lines	%
gnosis/eth/ethereum_client.py	1	86.16%
gnosis/safe/tests/utils.py	1	60.0%

Totals
Change from base Build 9302424802:	-0.02%
Covered Lines:	8068
Relevant Lines:	8629

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 9345962607

Details

• 112 of 112 (100.0%) changed or added relevant lines in 4 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.08%) to 93.599%

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Totals
Change from base Build 9317946988:	0.08%
Covered Lines:	8160
Relevant Lines:	8718

---

💛 - Coveralls

[Uxio0]

What are you returning? Maybe you can define a TypedDict (inside a file entities.py on the transaction_service_api/ folder) to make clear what's the return value. And we should do the same for other functions

[falvaradorodriguez]

You are right, I did this by looking at the other methods, but it is not the right thing to do. I will try to update the other method signatures.

[Uxio0]

You are not checking the function is returning anything. I could change return response.json() in decode_data function to return None at the end and this test will pass. You should also mock the result and check the function is returning what you expect.

[Uxio0]

Nice job